1. Field of the Invention
The present invention relates to an exposure quantity control method for controlling the exposure quantity with respect to a photosensitive substrate in an exposure apparatus used in a lithography process for manufacturing, for example, a semiconductor device, a liquid crystal display device, an image pickup device (e.g., CCD), or a thin film magnetic head.
In particular, the present invention is preferably used when exposure quantity control is effected in a scanning exposure type projection exposure apparatus such as that of step and scan type in which, while a part of a pattern on a mask is projected onto a photosensitive substrate, the mask and the substrate are scanned in synchronization with each-other with respect to its projection optical system so as to successively transfer the pattern of the mask to individual shot areas on the substrate.
2. Related Background Art
The exposure apparatus is an apparatus which projects a desired pattern onto a photosensitive material (photoresist). Such an exposure apparatus is disclosed in U.S. Pat. Nos. 4,908,656 and 5,191,374.